Research has shown that ‘job strain’ is linked an increased risk of heart attacks and deaths from coronary heart disease.
The risk to the heart is much smaller than for smoking or not exercising, the Lancet medical journal report said.
Therefore, how people reacted to work stress was key.
Working in any profession could lead to strain, but it is more common in lower skilled workers.
Doctors who have a lot of decision-making in their jobs would be less likely to have job strain than someone working on a busy factory production line.
There has previously been conflicting evidence on the effect of job strain on the heart.
One of the researchers, Prof Mika Kivimaki, from University College London, said: "Our findings indicate that job strain is associated with a small but consistent increased risk of experiencing a first coronary heart disease event, such as a heart attack."
The researchers said eliminating job strain would prevent 3.4% of those cases, whereas there would be a 36% reduction if everyone stopped smoking.
Prof Kivimaki said the evidence of a direct effect of job strain on the heart was mixed.
Job strain is linked to other lifestyle choices that were bad for the heart.
Smokers with job strain are more likely to smoke a bit more, active people with job strain are more likely to become inactive and there is a link with obesity.
If one has high stress at work you can still reduce risk by keeping a healthy lifestyle.
We know that being under stress at work, and being unable to change the situation, could increase your risk of developing heart disease.
The study also showed that the negative effect of workplace strain is much smaller than, for example, the damage caused by smoking or lack of exercise.
Though stresses at work may be unavoidable, how you deal with these pressures is important, and lighting up a cigarette is bad news for your heart.
Eating a balanced diet, taking regular exercise and quitting smoking will more than offset any risk associated with your job."
Bo Netterstrom, from Bispebjerg Hospital in Denmark, said other stresses at work such as job insecurity "are likely to be of major importance".
He said job strain was "a measure of only part of a psychosocially damaging work environment".